From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9D06BC54E58 for ; Wed, 20 Mar 2024 18:30:52 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AC5A110F6D9; Wed, 20 Mar 2024 18:30:47 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="WTN+vqMP"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.19]) by gabe.freedesktop.org (Postfix) with ESMTPS id D114710F6D9; Wed, 20 Mar 2024 18:30:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1710959446; x=1742495446; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=pIMvEZlWIVtjNJitQfBbhwqYFC5rypTGNigzi89FX0w=; b=WTN+vqMPzTJM/kWoh0KwasBgygzr2cTheP6jKAuS+ePKwDeZZWa/LNwR BxGp7XllMF35Im02i9smL7gip40BELnnHwr4KR6MlaXT8miioaAjNm0kw yDTJTkWSENwhf2RekBmllFCYxZUMeEKm7oSy6PPzcHk3q81gCPmfdoYlZ wjRK906FkLiTUWZRU/D5zA8TFyd9Kml7ArkQhPP56J99hSBnEQR6eYj2p i24lIWfOpUvMTTIUTgdn3sve7me/4EzlbeGe1dhsHPFtLNxSnQLGqsFnT MnGwxgmjv0a1MGupRnPpVFIpfzZjp55/bYqPMVnYEUl4J+XbZaAx5eyZ+ A==; X-IronPort-AV: E=McAfee;i="6600,9927,11019"; a="5754538" X-IronPort-AV: E=Sophos;i="6.07,140,1708416000"; d="scan'208";a="5754538" Received: from fmviesa008.fm.intel.com ([10.60.135.148]) by fmvoesa113.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2024 11:30:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,140,1708416000"; d="scan'208";a="14303213" Received: from unknown (HELO intel.com) ([10.247.118.186]) by fmviesa008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2024 11:30:33 -0700 Date: Wed, 20 Mar 2024 19:30:25 +0100 From: Andi Shyti To: "Mrozek, Michal" Cc: Andi Shyti , Nirmoy Das , "Landwerlin, Lionel G" , intel-gfx , dri-devel , Andi Shyti , "Hajda, Andrzej" , Chris Wilson , "Das, Nirmoy" , "stable@vger.kernel.org" Subject: Re: [PATCH] drm/i915/gt: Report full vm address range Message-ID: References: <20240313193907.95205-1-andi.shyti@linux.intel.com> <46ab1d25-5d16-4610-8b8f-2ee07064ec2e@intel.com> <35df0767-384f-49f2-806a-f83765ca7c4c@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" Hi Michal, On Mon, Mar 18, 2024 at 05:21:54AM +0000, Mrozek, Michal wrote: > > > Lionel, Michal, thoughts? > Compute UMD needs to know exact GTT total size. the problem is that we cannot apply the workaround without reserving one page from the GTT total size and we need to apply the workaround. If we provide the total GTT size we will have one page that will be contended between kernel and userspace and, if userspace is unaware that the page belongs to the kernel, we might step on each other toe. The ask here from kernel side is to relax the check on the maxNBitValue() in userspace and take what the kernel provides. Thanks, Andi